1. Field of the Invention
The present invention relates generally to medical methods and devices. More particularly, the present invention relates to methods and devices for the endovascular placement of a stent-graft from an artery, through an adjacent vein, and back to the artery in order to bypass an occlusion in the artery, typically a femoral artery.
Peripheral arterial occlusive disease results from atherosclerotic processes which cause a blockage or stenosis within a peripheral artery, typically a femoral artery, most commonly the superficial femoral artery. As the disease progresses, resistance to blood flow down the patient's leg reduces distal perfusion of the leg. In the most severe cases, the disease can lead to limb ischemia which can have serious complications, including gangrene and loss of the leg.
Peripheral arterial occlusive disease in the femoral artery can be treated in many of the same ways as arterial disease elsewhere in the body. Endarterectomy and atherectomy can both be used to remove the occlusive deposits and restore blood flow. Bypass grafts may also be placed from a location proximal to the occlusion to a location distal to the occlusion in order to provide an unobstructed path for blood to flow in the artery. Such bypass grafts are most commonly placed in open vascular surgeries where the bypass grafts may be attached to the femoral or other artery by conventional anastomic connections. More recently, it has been proposed to perform such procedures endovascularly to place a bypass stent-graft from the artery, through an adjacent vein, and back to the artery in order to bypass the occlusion.
Of particular interest to the present invention, Dr. James Joye has performed such endovascular stent-graft bypass procedures using commercially available catheters and tools.
While such protocols are very effective in the hands of a highly skilled vascular surgeon, they are lengthy, can be difficult to perform, and many surgeons would not feel confident trying to perform these procedures using conventionally available catheters and tools. For these reasons, it would be desirable to provide improved protocols and specialized catheters and surgical tools which reduce the technical difficulty of performing such endovascular stent-graft femoral bypass procedures. At least some of these objectives will be met by the inventions described herein below.
2. Description of the Background Art
Systems and methods for placing stent-grafts for bypassing peripheral and other occlusions are described in U.S. Pat. Nos. 5,078,735 and 5,211,683. A particular method for performing an external femoropopliteal bypass graft is described in WO2007/127802 and US 2010/0036475. U.S. Pat. Nos. 6,464,665 and 7,374,567, both describe catheters useful for capturing a needle and placing a stent across adjacent vessels. Other relevant patents include U.S. Pat. Nos. 5,830,222; 6,068,638; 6,190,353; 6,231,587; 6,379,319; 6,475,226; 6,508,824; 6,544,230; 6,655,386; 6,579,311; 6,585,650; 6,694,983; 6,719,725; 6,976,990; 7,004,173; 7,083,631; 7,134,438; 7,316,655; and 7,729,738.